Abusive player

I have a problem with a player. I explain: I'm about to win a game, here is the last move for the checkmate, but the player is not moving and he is waiting for losing by time. If I win by time, I think the points will be a few and this is not fairplay. What can I do?

It doesn't matter how you win/lose/draw. The rating change is based on the ratings of the players and their rating deviation values. 

As to them letting it time out, players get flagged for it and if they do it too often get restricted:

https://support.chess.com/customer/en/portal/articles/1444922-fair-play-policy

thank you very much

I would like to report a abusive player he just used very inappropriate language in chat ...

https://support.chess.com/customer/en/portal/articles/1444785-my-opponent-said-some-very-abusive-and-rude-things-what-should-i-do-

Hello,

Today I had a very bad experience with my last opponent. We played a 5 5 inc game and my oppenent played very fast but not so god. After a while he was totally lost in and endgame with an Exchange and pawns up for me. Then he sudently stopped moving for more than 4 minutes. Then I asked im if it was that bad losing a chessgame. Imidately he moved an sent me a message in translation "[removed, please don't recreate expletives in the forums -- VP]". I made my move and he let his time go out. I have met some abusive players Before here but this one was definitely the worst kind. Regards, Bengt

Sorry that happened to you. Some people have no class. (And the sad thing is that it'll only get worse from here on out. At least you can report 'em, though)

A good way to handle abusive players is to immediately block them at the first sign of abuse.  Don't even reply.  If it's extreme report it and let the mods handle it.

Never wrestle with a pig because you'll both get dirty and the pig will enjoy it.

I left out part of the saying.  It's "Never wrestle with a pig in the mud.  You'll both get dirty and the pig will enjoy it."